Magnetic resonance imaging in traumatic posterior hip dislocation

The objective was to report the ability of a magnetic resonance image to document the integrity of the obturator externus tendon after posterior hip dislocation as a potential predictor for preserved femoral head vascularity.

Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC), after slipped capital femoral epiphysis

OBJECTIVE: The aim of this study was to assess the glycosaminoglycan (GAG) content in hip joint cartilage in mature hips with a history of slipped capital femoral epiphysis (SCFE) using delayed gadolinium-enhanced MRI of cartilage (dGEMRIC). METHODS: 28 young-adult subjects (32 hips) with a mean age of 23.8+/-4.0 years (range: 18.1-30.5 years) who were treated for mild or moderate SCFE in adolescence were included into the study. Hip function and clinical symptoms were evaluated with the Harris hip score (HHS) system at the time of MRI. Plain radiographic evaluation included Tonnis grading, measurement of the minimal joint space width (JSW) and alpha-angle measurement. The alpha-angle values were used to classify three sub-groups: group 1=subjects with normal femoral head-neck offset (alpha-angle <50 degrees ), group 2=subjects with mild offset decrease (alpha-angle 50 degrees -60 degrees ), and group 3=subjects with severe offset decrease (alpha-angle >60 degrees ). RESULTS: There was statistically significant difference noted for the T1(Gd) values, lateral and central, between group 1 and group 3 (p-values=0.038 and 0.041). The T1(Gd) values measured within the lateral portion were slightly lower compared with the T1(Gd) values measured within the central portion that was at a statistically significance level (p-value <0.001). HHS, Tonnis grades and JSW revealed no statistically significant difference. CONCLUSION: By using dGEMRIC in the mid-term follow-up of SCFE we were able to reveal degenerative changes even in the absence of joint space narrowing that seem to be related to the degree of offset pathology. The dGEMRIC technique may be a potential diagnostic modality in the follow-up evaluation of SCFE.

Pros and cons of post-mortem CT imaging on aspiration diagnosis

Recently, the field of forensics has experienced a rapid increase in the use of modern cross-sectional imaging in forensic investigations. We examined the value of post-mortem computed tomography (CT) imaging relative to autopsy for distinguishing aspiration into the lungs from airways, from lung alterations due to other causes, and for identifying the aspirated material. We selected 54 bodies submitted to whole-body CT scanning prior to autopsy. All cases had autopsy findings of blood (31 cases), fresh water (12 cases), or gastric content (11 cases) aspiration. The radiological images were retrospectively analyzed for airway and lung aspiration. In all cases, CT imaging detected pulmonary abnormalities suggestive of aspiration. Nevertheless, analysis of the CT images alone was not able to identify the aspirated material or to distinguish pulmonary findings of aspiration from lung changes due to other causes, except for a few cases of hemo-aspiration. However, due to its ability to visualize the entire parenchyma, CT imaging was superior to autopsy in providing additional data about the distribution and severity of the aspiration as well as in detecting small abnormalities. Post-mortem CT imaging should be considered as a superior tool for forensic investigations of aspiration due to its ability to document diagnostic conclusions and to guide the forensic pathologist during lung tissue examination.

Meningial perineurioma: a benign peripheral nerve sheath tumor in a previously unrecognized central nervous system location, mimicking meningioma

Perineurioma is an uncommon, mostly benign, spindle-cell tumor of peripheral nerve sheath origin with a predilection for the soft tissues. Although increasing awareness points to the sites of involvement by perineurioma possibly being as ubiquitous as those frequented by schwannian tumors, only one intracerebral example has been described to date. We report on a surgically resected perineurioma of the falx cerebri in an 86-year-old woman. Preoperative imaging showed an enhancing extraaxial mass of 6 cm × 5.7 cm × 3.7 cm. Histologically, the tumor consisted of a proliferation of spindle cells interwoven by a lattice of basal lamina. Alongside a prevailing soft tissue perineurioma pattern, sclerosing and reticular areas were seen as well. Tumor cells coexpressed EMA and GLUT-1, and a minority immunoreacted for smooth muscle actin. Pericellular basal lamina was decorated with collagen type IV. No staining for S100 protein was detected. Mitotic activity was virtually absent, and the MIB1 labeling index averaged 2%. Ultrastructural examination revealed abundant pinocytotic vesicles within and conspicuous tight junctions between slender cytoplasmic processes which, in turn, were encased by discontinuous basal lamina. FISH analysis confirmed loss of at least part of one chromosome 22q. This observation calls attention to perineurioma as a novel item in the repertoire of low-grade meningial spindle cell neoplasms, in the differential diagnostic context of which it is apt to being misconstrued as either meningioma, solitary fibrous tumor, or neurofibroma. Confusion with the latter bears the risk of overgrading innocuous features of perineurioma as criteria for malignancy.

Percutaneous radiofrequency ablation of virtual tumours in canine kidney using Global Positioning System-like technology

What's known on the subject? And what does the study add? We have previously shown that percutaneous radiofrequency ablation guided by image-fusion technology allows for precise needle placement with real time ultrasound superimposed with pre-loaded imaging, removing the need for real-time CT or MR guidance. Emerging technology also allows real-time tracking of a treatment needle within an organ in a virtually created 3D format. To our knowledge, this is the first study utilising a sophisticated ultrasound-based navigation system that uses both image-fusion and real-time probe-tracking technologies for in-vivo renal ablative intervention.

Massive Systemic Fat Embolism Detected by Postmortem Imaging and Biopsy

Postmortem computed tomography (pmCT) and pmCT angiography (pmCTA) provide a minimally invasive method to determine the cause of death. Postmortem image-guided biopsy allows for precise sampling of histological specimens. This case study describes the findings of lethal systemic fat embolism (FE) on whole-body unenhanced pmCT, pmCTA, and image-guided biopsy, with autopsy and histopathologic correlation. Unenhanced pmCT revealed a distinct fat level on top of sedimented layers of corpuscular blood particles and serum in the arterial system and pulmonary trunk. Subsequent pmCTA showed reproducible results, and image-guided biopsy confirmed fatal FE. pm CT/pmCTA combined with image-guided biopsy established the cause of death as right heart failure as a result of systemic fatal FE prior to autopsy. All imaging findings were consistent with traditional autopsy and histological specimens. This unique case demonstrates new imaging findings in massive, fatal FE and highlights that postmortem imaging, supplemented by image-guided biopsy, may detect the cause of death prior to traditional autopsy.

A 20-channel receive-only mouse array coil for a 3 T clinical MRI system

A 20-channel phased-array coil for MRI of mice has been designed, constructed, and validated with bench measurements and high-resolution accelerated imaging. The technical challenges of designing a small, high density array have been overcome using individual small-diameter coil elements arranged on a cylinder in a hexagonal overlapping design with adjacent low impedance preamplifiers to further decouple the array elements. Signal-to-noise ratio (SNR) and noise amplification in accelerated imaging were simulated and quantitatively evaluated in phantoms and in vivo mouse images. Comparison between the 20-channel mouse array and a length-matched quadrature driven small animal birdcage coil showed an SNR increase at the periphery and in the center of the phantom of 3- and 1.3-fold, respectively. Comparison with a shorter but SNR-optimized birdcage coil (aspect ratio 1:1 and only half mouse coverage) showed an SNR gain of twofold at the edge of the phantom and similar SNR in the center. G-factor measurements indicate that the coil is well suited to acquire highly accelerated images.

Discovering imaging endophenotypes for major depression

Psychiatry research lacks an in-depth understanding of mood disorders phenotypes, leading to limited success of genetics studies of major depressive disorder (MDD). The dramatic progress in safe and affordable magnetic resonance-based imaging methods has the potential to identify subtle abnormalities of neural structures, connectivity and function in mood disordered subjects. This review paper presents strategies to improve the phenotypic definition of MDD by proposing imaging endophenotypes derived from magnetic resonance spectroscopy measures, such as cortical gamma-amino butyric acid (GABA) and glutamate/glutamine concentrations, and from measures of resting-state activity and functional connectivity. The proposed endophenotypes are discussed regarding specificity, mood state-independence, heritability, familiarity, clinical relevance and possible associations with candidate genes. By improving phenotypic definitions, the discovery of new imaging endophenotypes will increase the power of candidate gene and genome-wide associations studies. It will also help to develop and evaluate novel therapeutic treatments and enable clinicians to apply individually tailored therapeutic approaches. Finally, improvements of the phenotypic definition of MDD based on neuroimaging measures will contribute to a new classification system of mood disorders based on etiology and pathophysiology.

Dopaminergic modulation of the human reward system: a placebo-controlled dopamine depletion fMRI study

Reward related behaviour is linked to dopaminergic neurotransmission. Our aim was to gain insight into dopaminergic involvement in the human reward system. Combining functional magnetic resonance imaging with dopaminergic depletion by α-methylparatyrosine we measured dopamine-related brain activity in 10 healthy volunteers. In addition to blood-oxygen-level-dependent (BOLD) contrast we assessed the effect of dopaminergic depletion on prolactin response, peripheral markers for dopamine and norepinephrine. In the placebo condition we found increased activation in the left caudate and left cingulate gyrus during anticipation of reward. In the α-methylparatyrosine condition there was no significant brain activation during anticipation of reward or loss. In α-methylparatyrosine, anticipation of reward vs. loss increased activation in the right insula, left frontal, right parietal cortices and right cingulate gyrus. Comparing placebo versus α-methylparatyrosine showed increased activation in the left cingulate gyrus during anticipation of reward and the left medial frontal gyrus during anticipation of loss. α-methylparatyrosine reduced levels of dopamine in urine and homovanillic acid in plasma and increased prolactin. No significant effect of α-methylparatyrosine was found on norepinephrine markers. Our findings implicate distinct patterns of BOLD underlying reward processing following dopamine depletion, suggesting a role of dopaminergic neurotransmission for anticipation of monetary reward.

A global ”imaging” view on systems approaches in immunology

The immune system exhibits an enormous complexity. High throughput methods such as the "-omic'' technologies generate vast amounts of data that facilitate dissection of immunological processes at ever finer resolution. Using high-resolution data-driven systems analysis, causal relationships between complex molecular processes and particular immunological phenotypes can be constructed. However, processes in tissues, organs, and the organism itself (so-called higher level processes) also control and regulate the molecular (lower level) processes. Reverse systems engineering approaches, which focus on the examination of the structure, dynamics and control of the immune system, can help to understand the construction principles of the immune system. Such integrative mechanistic models can properly describe, explain, and predict the behavior of the immune system in health and disease by combining both higher and lower level processes. Moving from molecular and cellular levels to a multiscale systems understanding requires the development of methodologies that integrate data from different biological levels into multiscale mechanistic models. In particular, 3D imaging techniques and 4D modeling of the spatiotemporal dynamics of immune processes within lymphoid tissues are central for such integrative approaches. Both dynamic and global organ imaging technologies will be instrumental in facilitating comprehensive multiscale systems immunology analyses as discussed in this review.

Effects of doxorubicin cancer therapy on autophagy and the ubiquitin-proteasome system in long-term cultured adult rat cardiomyocytes

The clinical use of anthracyclines in cancer therapy is limited by dose-dependent cardiotoxicity that involves cardiomyocyte injury and death. We have tested the hypothesis that anthracyclines affect protein degradation pathways in adult cardiomyocytes. To this aim, we assessed the effects of doxorubicin (Doxo) on apoptosis, autophagy and the proteasome/ubiquitin system in long-term cultured adult rat cardiomyocytes. Accumulation of poly-ubiquitinated proteins, increase of cathepsin-D-positive lysosomes and myofibrillar degradation were observed in Doxo-treated cardiomyocytes. Chymotrypsin-like activity of the proteasome was initially increased and then inhibited by Doxo over a time-course of 48 h. Proteasome 20S proteins were down-regulated by higher doses of Doxo. The expression of MURF-1, an ubiquitin-ligase specifically targeting myofibrillar proteins, was suppressed by Doxo at all concentrations measured. Microtubule-associated protein 1 light chain 3B (LC3)-positive punctae and both LC3-I and -II proteins were induced by Doxo in a dose-dependent manner, as confirmed by using lentiviral expression of green fluorescence protein bound to LC3 and live imaging. The lysosomotropic drug chloroquine led to autophagosome accumulation, which increased with concomitant Doxo treatment indicating enhanced autophagic flux. We conclude that Doxo causes a downregulation of the protein degradation machinery of cardiomyocytes with a resulting accumulation of poly-ubiquitinated proteins and autophagosomes. Although autophagy is initially stimulated as a compensatory response to cytotoxic stress, it is followed by apoptosis and necrosis at higher doses and longer exposure times. This mechanism might contribute to the late cardiotoxicity of anthracyclines by accelerated aging of the postmitotic adult cardiomyocytes and to the susceptibility of the aging heart to anthracycline cancer therapy.

Classification of acute and delayed contrast media-induced reactions: proposal of a three-step system

Physicians and scientists use a broad spectrum of terms to classify contrast media (CM)-induced adverse reactions. In particular, the designation of hypersensitivity reactions is quite varied. Consequently, comparisons of different papers dealing with this subject are difficult or even impossible. Moreover, general descriptions may lead to problems in understanding reactions in patients with a history of adverse CM-reactions, and in efficiently managing these patients. Therefore, the goal of this paper is to suggest an easy system to clearly classify these reactions. The proposed three-step systems (3SS) is built up as follows: step 1 exactly describes the clinical features, including their severity; step 2 categorizes the time point of the onset (immediate or nonimmediate); and step 3 generally classifies the reaction (hypersensitivity or nonhypersensitivity reaction). The 3SS may facilitate better understanding of the clinical manifestations of adverse CM reactions and may support the prevention of these reactions on the basis of personalized medicine approaches.

Interdisciplinary expert consensus document on management of type B aortic dissection

An expert multidisciplinary panel in the treatment of type B aortic dissection reviewed available literature to develop treatment algorithms using a consensus method. Data from 63 studies published from 2006 to 2012 were retrieved for a total of 1,548 patients treated medically, 1,706 patients who underwent open surgery, and 3,457 patients who underwent thoracic endovascular repair (TEVAR). For acute (first 2 weeks) type B aortic dissection, the pooled early mortality rate was 6.4% with medical treatment and increased to 10.2% with TEVAR and 17.5% with open surgery, mostly for complicated cases. Limited data for treatment of subacute (2 to 6 weeks after onset) type B aortic dissection showed an early mortality rate of 2.8% with TEVAR. In chronic (after 6 weeks) type B aortic dissection, 5-year survival of 60% to 80% was expected with medical therapy because complications were likely. If interventional treatment was applied, the pooled early mortality rate was 6.6% with TEVAR and 8.0% with open surgery. Medical treatment of uncomplicated acute, subacute, and chronic type B aortic dissection is managed with close image monitoring. Hemodynamic instability, organ malperfusion, increasing periaortic hematoma, and hemorrhagic pleural effusion on imaging identify patients with complicated acute type B aortic dissection requiring urgent aortic repair. Recurrence of symptoms, aortic aneurysmal dilation (>55 mm), or a yearly increase of >4 mm after the acute phase are predictors of adverse outcome and need for delayed aortic repair ("complicated chronic aortic dissections"). The expert panel is aware that this consensus document provides proposal for strategies based on nonrobust evidence for management of type B aortic dissection, and that literature results were largely heterogeneous and should be interpreted cautiously.

Live cell imaging techniques to study T cell trafficking across the blood-brain barrier in vitro and in vivo

BACKGROUND The central nervous system (CNS) is an immunologically privileged site to which access for circulating immune cells is tightly controlled by the endothelial blood-brain barrier (BBB) located in CNS microvessels. Under physiological conditions immune cell migration across the BBB is low. However, in neuroinflammatory diseases such as multiple sclerosis, many immune cells can cross the BBB and cause neurological symptoms. Extravasation of circulating immune cells is a multi-step process that is regulated by the sequential interaction of different adhesion and signaling molecules on the immune cells and on the endothelium. The specialized barrier characteristics of the BBB, therefore, imply the existence of unique mechanisms for immune cell migration across the BBB.

Intersection of Tradition and Need of Change in Romanian Child Protection System

The reconstruction of the child protection system in the post-communist period so as to meet professional standards while responding to the needs of children is an enormous task. In order to understand the features of the current stage of the development of the Romanian child protection system and to evaluate its trends towards change, Roth-Szamoskozi analysed data from scientific literature and collected statistics to document the evolution of the child-protection structure. Empirical data collection using qualitative methods (content analysis of documents and interviews with staff) were designed to reflect the degree to which child welfare laws correspond to internationally accepted regulations and to analyse the attitudes of those working in the field at different decision-making levels. An experiment with a group of 12 students showed that there have been basic changes in the legal framework of Romanian child welfare. Students could see that the required principles exist in the new Romanian child protection law, but also identified areas which are still inadequately represented. 61 staff members working in child welfare agencies (both state and non-governmental) were also interviewed, using a systematic, circular interview. Using the criteria of competence and the existence of specific social goals, professionalism in solving social problems and respect for social-work values, the 30 non-governmental organisations were divided into three categories. The first (7 organisations) are active in the area, know the law and are fairly professional, the second (5) are motivated in their work with specific problems, but with no great competence. The 18 organisations in the third group have no competence in the social field and in issues concerning children and do only charitable work. The state agencies are still dominated by routine, but there were many staff members who were developing reform and strategic roles and were actively directing the system towards change. Many staff members in both governmental and non-governmental organisations were directing the system towards a stress on intervention in the interests of the child in the context of its family. Roth-Szamoskozi found that staff members felt the need of a more accurate evaluation system which would enable them to show their results more clearly.